Related Experiment Video
Updated: Jun 23, 2025
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Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
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Asymmetric ion transport through "Janus" MoSSe sub-nanometer pores
Rajat Chakraborty1,2, Henry T Crawford-Eng1, Jean-Pierre Leburton1,2,3
1Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. jleburto@illinois.edu.
Nanoscale
|June 24, 2024
Summary
Janus MoSSe membranes with sub-nanometer pores exhibit tunable ion transport. Negative charges and bias polarity control ion adsorption and current flow, offering potential for selective ion filtering applications.
Area of Science:
- Materials Science
- Computational Chemistry
- Nanotechnology
Background:
- Ion transport through sub-nanometer pores is crucial for applications like desalination and sensing.
- Janus materials, with differing properties on each side, offer unique functionalities.
- Molybdenum disulfide selenide (MoSSe) is a promising 2D material for advanced applications.
Purpose of the Study:
- To investigate ion transport mechanisms through negatively charged sub-nanometer pores in Janus MoSSe membranes.
- To understand the influence of charge configuration and external bias on ion adsorption and translocation.
- To explore the effect of multi-layered Janus membranes on ion current control.
Main Methods:
- All-atom molecular dynamics simulations were employed.
- Systematic investigation of ion adsorption, desorption, and translocation times.
- Analysis of ionic current-voltage (I-V) characteristics under varying bias polarities and pore charges.
Main Results:
- Charge imbalance in Janus MoSSe pores induces asymmetric ion adsorption and I-V characteristics.
- Potassium ions predominantly adsorb before translocating, with dwell times influenced by pore charges.
- High biases suppress adsorption, enhancing translocation, especially with negative pore charges.
- Ionic current control is achieved by increasing the number of Janus layers, raising the pore barrier.
Conclusions:
- Janus MoSSe membranes with tailored pore charges offer a mechanism for controlling ion transport.
- The observed asymmetry and bias-dependent behavior are key to understanding ion selectivity.
- Multi-layered Janus structures provide a tunable platform for advanced ion filtering and energy applications.
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